I agree w/woundedfool, step back for a bit. I know you are upset w/him for not calling you, but you can off a bit like his mother or the warden. So, if he doesn't call you, let it go and continue on doing things for yourself. He's a big boy and he can take care of himself. If you give ultimatums, he will pick the one w/least work.
Yes, you are spouting off here and this is good, but I think I would cool my jets a bit and I'm going to ask you this...are you really, really ready to have him leave the home? Especially this close to Christmas? Do you want this type of memory hanging around you memory bank each and every year? I can tell you...the date will remind you of how upsetting your holiday would be for a very long time. My xh walked out the final time December 13th and it took me a very long time not to look at that date each year and remember what he did. Step back, cool your jets for a while.
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.